Oil and gas producer Santos says Australia's first commercial shale gas well is ready to go into production, helping to boost supply and keep prices stable in eastern Australia.

Santos said its Moomba-191 well in the Cooper Basin was now producing dry gas after the company reported an increase in underlying first half profit and maintained its full-year production guidance on Friday. ...

Chief executive David Knox said shale gas flows from the Moomba well were a significant milestone in the company's program to unlock the vast unconventional gas potential of the Cooper Basin that straddles the South Australian and Queensland border.

"The shale well result has been an outstanding result for us and potentially for eastern Australia for the very long-term future," Mr Knox told analysts on Friday. ...

"The share price is up because of the surprisingly good flow rate that they're getting at their Moomba 191 shale gas well," Mr Wood said. "You can start to talk about some very large numbers on the back of that, but it's very early days. Certainly this flow rate was better than we were expecting."